Iodine perchlorates

ABSTRACT

Iodine perchlorates of the formula X(OClO3)n wherein X is selected from the group consisting of I 115 and CsI 4, wherein n equals 3 when X is I and n equals 4 when X is CsI 4; are prepared by reacting ClOClO3 with either solid I or CsI at low temperatures. The iodine perchlorates are useful as energetic oxidizers.

United States Patent [191 Christe et a1.

[ lODlNE PERCHLORATES [75] Inventors: Karl O. Christe, Calabasas; Carl J.

Schack, Chatsworth, both of Calif.

[73] Assignee: The United states of America as represented by the Secretary of the Navy, Washington, DC.

221 Filed: Mar. 18, 1975 21 Appl. No.: 559,601

Related US. Application Data [62] Division of Ser. No. 363,708, May 24, 1973, Pat. No.

[56] References Cited UNITED STATES PATENTS 3,694,172 9/1972 Shack et a1. 423/466 [4 Nov. 25, 1975 3,873,677 3/1975 Christe et'al. 423/466 OTHER PUBLICATIONS Mellors Modern Inorganic Chemistry, Rev. Ed. by G. D. Parkes, 1951, p. 540. Longmans, Green & Co., New York.

Primary Examiner-Edward Stern Attorney, Agent, or Firm-R. S. Sciascia; .1. A. Cooke [57] ABSTRACT Iodine perchlorates of the formula X(OC1O wherein X is selected from the group consisting of l l15 and Csl, wherein n equals 3 when X is I and n equals 4 when X is Csl; are prepared by reacting ClOClO with either solid 1 or Csl at low temperatures. The iodine perchlorates are useful as energetic oxidizers.

3 Claims, N0 Drawings IODINE PERCHLORATES This is a division of application Ser. No. 363,708, filed May 24, 1973, now U.S. Pat. No. 3,873,677, issued Mar. 25, 1975.

BACKGROUND OF THE INVENTION This invention generally relates to perchlorate compounds and more particularly to iodine perchlorates.

The alleged preparation of iodine trisperchlorate from iodine, ozone, and anhydrous I-IClO is described by M. Schmeisser in Handbook of Preparative Inorganic Chemistry, G. Brauer, Ed., Academic Press, New York, N.Y., 1963, Vol. 1, pg. 330. However, a crosscheck with the original publication, F. Fichter and H. Kappeler, Z. Anorg. Allgem. Chem., 91, 134 (1915), reveals that the original paper deals only with a compound having the empirical composition, I(CI- O 2I-I- O. Further, from the properties of I(OCIO it appears unlikely that the Fichter et a1 compound was the bishydrate of I(OClO The bishydrate of iodine trisperchlorate, I(OCIO 'ZH O, should be a less energetic oxidizer than the anhydrous form, and therefore would be less suitable for propellants. In view of this attempts have been made to obtain the bishydrate as well as the anhydrous material.

SUMMARY OF THE INVENTION Accordingly, one object of this invention is to provide iodine perchlorates.

Another object of this invention is to isolate iodine perchlorates in their solid anhydrous form.

A further object of this invention is to provide iodine perchlorates which are highly energetic oxidizers.

A still further object of this invention is to provide a method of synthesizing iodine perchlorates.

Still another object of this invention is to achieve a high degree of purity in the iodine perchlorates synthesized.

Yet another object is to provide a easy means of purifying the iodine perchlorates.

These and other objects of this invention are accomplished by providing compounds which are iodine perchlorates of the formula X(CIO wherein X is selected from the group consisting of I and Csl wherein n equals 3 when X is 1*, and n equals 4 when X is Csl. The iodine perchlorates are prepared by reacting chlorine perchlorate, CIOCIO with a substance selected from the group consisting of and Csl at low temperatures.

DESCRIPTION OF THE PREFERRED EMBODIMENT The iodine perchlorates of this invention are prepared by reacting chlorine perchlorate, CIOCIO with either iodine, 1;, or Csl. The reaction for preparing iodine trisperchlorate is as follows:

I, 6CIOCIO, 2l(oclo,), SCI,

and the reaction for preparing the cesium tetraperchlorato iodate is as follows: Cs 1 4ClOClO Cs 1(OClO- 20:.

The range of suitable reaction temperatures is limited by the slow reaction rates and the instability of the iodine perchlorate products. For example, the iodine trisperchlorate reaction takes 70 hours at50C and the cesium tetraperchlorato iodate reaction takes 5 weeks at 45C to go to 99% completion and at lower temper- 2 atures the reaction 'takes still longer. On the other hand, while the Csl(OClO is stable at 23C, iodine trisperchlorate rapidly decomposes, at this temperature.

Thus, the reaction temperature for producing CsI(O- ClO should be in the range 7 8C to 30C, preferably 55C to 40C; and the reaction temperature for producing iodine trisperchlorate should be in the range 7 8C to 0, preferably 55C to -40C.

Purification of the product is simplified by reacting a stoichiometric excess of chlorine perchlorate with iodine or cesium iodide in an inert environment. The excess of chlorine perchlorate is used to drive the reaction to 99% completion. Then the solid I(OClO or CsI(OClO product can be separated from the byproduct chlorine and unreacted chlorine perchlorate at low temperatures under vacuum. Finally, since water is neither a reactant nor a product in either of the reactions, the anhydrous form of I(OClO or CsI(OClO is obtained when the reaction is run in an anhydrous environment. Additionally, because of the reactivity of the desired perchlorates it is most desirable to conduct the reactions in an inert environment which, within the context of this invention, is meant to include anhydrous conditions.

The general nature of the invention having been set forth, the following examples are presented as specific illustrations thereof. It will be understood that the invention is not limited to these specific examples but is susceptible to various modifications that will be recognized by one of ordinary skill in the art.

EXAMPLE 1 Iodine Trisperchlorate I(OCIO Iodine (0.915 mmol) was loaded into a 10 m1 prepassivated Teflon FEP ampoule closed off by a stainless steel valve. Chlorine perchlorate (8.18 mmol) was added at 196C. The ampoule was kept at 50C for hours. At this point, the dark iodine color had disappeared and a pale yellow (clue to the presence of C1,) solid had formed. Upon cooling to 196C, the ampoule did not contain any non-condensible reaction products. The ampoule was slowly warmed to 45C. The volatile products were separated by fractional condensation and identified by infrared spectroscopy and their vapor pressure. They consisted of C1 (2.70 mmol) and ClOClO (2.74 mmol). The white, solid residue weighed 776 mg., in excellent agreement with the weight (777 mg) calculated for a complete conversion to I(OClO EXAMPLE 2 Cesium Tetraperchlorato Iodate (III) CsI(OClO A 10 ml prepassivated stainless steel cylinder was loaded with powdered anhydrous Csl (1.15 mmol), followed by ClOClO (6.10 mmol) at l96C. The reaction was allowed to proceed by warming the cylinder to 45C, where it was maintained for five weeks. On recooling to l96C, no non-condensible gases were observed. Volatile products were pumped from the reactor for several hours while and after it had warmed to ambient temperature. Separation of these species was affected by fractional condensation and identification by infrared and vapor pressure measurements. They consisted of C1 (2.34 mmol) and unreacted ClOClO (1.45rnmol). The solid product was pale yellow in color and weighed 749 mg, indicating a 99% conversion of the CS1 to C+I(OC1O3)4* had occurred.

Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described herein.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. A method of preparing anhydrous iodine trisperchlorate, l(OClO comprising:

4 contacting in an inert environment chlorine perchlo rate and iodine at a temperature in the. range of -7 8C to 0C for or more hours, provided that at least 6 moles of chlorine perchlorate are used per mole of iodine, l to form said iodine trisper-,

chlorate and subsequently recovering the iodine trisperchlorate.

2. The method of claim 1, wherein said contacting is performed at a temperature of 5 5C to -40C. I

3. The method of claim I, wherein more than 6 moles i of said chlorine perchlorate is used per mole of iodine, 2. I 

1. A METHOD OF PREPARING ANHYDROUS IODINE TRISPERCHLORATE, I(OCIO3)3, COMPRISING: CONTACTING IN AN INERT ENVIRONMENT CHLORINE PERCHLORATE AND IODINE AT A TEMPERATURE IN THE RANGE OF -78*C TO 0*C FOR 70 OR MORE HOURS, PROVIDED THAT AT LEAST 6 MOLES OF CHLORINE PERCHLORATE ARE USED PER MOLE OF IODINE, I2, TO FORM SAID IODINE TRISPERCHLORATE AND SUBSEQUENTLY RECOVERING THE IODINE TRISPERCHLORATE.
 2. The method of claim 1, wherein said contacting is performed at a temperature of -55*C to -40*C.
 3. The method of claim 1, wherein more than 6 moles of said chlorine perchlorate is used per mole of iodine, I2. 